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YORKVILLE - Synergy 2x 21” Powered Subwoofer Dual 21" Bass Reflex Powered Subwoofer: 6000 watts (program), 17,000 watts (peak) 2 x 21-inch LF woofers with 4.5-inch voice coils. Exceptionally high output and deep bass.

Marsoni M251S
Sale price$3449.50
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YORKVILLE - Synergy 2x 21” Powered Subwoofer Dual 21" Bass Reflex Powered Subwoofer: 6000 watts (program), 17,000 watts (peak) 2 x 21-inch LF woofers with 4.5-inch voice coils. Exceptionally high output and deep bass.This powerful dual 21 inch subwoofer offers the highest peak power and deepest bass response of any speaker in the Synergy series, Yorkville Sounds largest and most powerful point source system. The SA221S can be combined with an SA153 as an independent system, or with the SA153 and SA315S as a 5 way system. If it were any more powerful, it would have to be measured on the Richter scale. Features 17000 W Peak Power (6000 W Program) 2x 21 Neodymium
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4.2 ★★★★★
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Review Dude
Massapequa, US
★★★★★ 5
#1 for #2's
Flavor Name: Unflavored, Size: 1.46 Pound (Pack of 1)
I like the lack of sweeteners and flavor. I just want the stuff that helps me poop. There is some citric acid in it (no idea why) which gives it a mildly acidic taste. Other than that, it does the trick.
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Reviewed in the United States on March 23, 2026
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Strathmont
Bozeman, US
★★★★★ 5
Good Stuff
Flavor Name: Unflavored, Size: 1.46 Pound (Pack of 1)
If you need more fiber in your diet, you need this. The price is right, it works very well and keeps me regular. I use this instead of the gummies or capsules. That's because you MUST put in in fluid, and hydration is SO important when using a psyllium product as it causes water to be absorbed very quickly once it is ingested, and you don't want to dehydrate! Mixes very well in water and has little to no taste whatsoever. Stay regular, stay hydrated and stay well.
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Reviewed in the United States on April 14, 2026
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Robert
Birmingham, US
★★★★★ 4
Works well, but is now too expensive...
Flavor Name: Unflavored, Size: 1.46 Pound (Pack of 1)
The "No added sweeteners" has been my go-to version of Metamucil, but I'm giving it 4 stars and moving on to another brand as the price is over $35 which is too much imo...
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Reviewed in the United States on October 15, 2025
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S. E. Seater
Port Orchard, US
★★★★★ 5
I like the mildly tart taste of this unflavored, unsweetened drink made up with water.
Flavor Name: Unflavored, Size: 1.46 Pound (Pack of 1)
I like the mildly tart taste of this unflavored, unsweetened drink made up with water. The texture doesn't bother me, with stirring right from the beginning of adding the water, there is no clumping. After 10 days there is no effect on my bowels which were regular previously anyway. My doctor wanted me to use this although I already have a high fiber diet.
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Reviewed in the United States on April 25, 2026
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AB
Charlottesville, US
★★★★★ 1
Definitely Not Unflavored. This is Tart / Sour, Which Limits the Options to Certain Juices
Flavor Name: Unflavored, Size: 1.46 Pound (Pack of 1)
I was expecting an unflavored fiber powder. However, expect a sour/tart taste. This means you can't add it to tea or coffee. I don't think it is appropriate to say that it is "unflavored" as I've had psyllium husk from other vendors that are truly "unflavored" (i.e. no citric acid). Dextrin (another fiber source) is also unflavored. But this Metamucil is tart (like sucking a lime) and can only be added to tart juices like orange juice or lemonade.
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Reviewed in the United States on May 19, 2026

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